Dirty stone tools reveal the Pleistocene diet.
The hominins living in Azraq, Jordan 250,000 years ago had a bad habit of not washing their meat-carving tools after dinner. Those dirty stone tools have now become the subject of a study, published in the Journal of Archaeological Science, in which researchers attempted to figure out what exactly was on the menu for hominins at the end of the Pleistocene.
Analysis of protein residues on 17 of the 44 tools selected for testing suggested they were hunting and feasting on a variety of species. The smorgasbord featured rhinoceros, camel, duck, bovine and horse.
The tools provide more than a record of a prehistoric dinner menu. They also give insight into a curious behaviour — each tool tested positive for a single species, suggesting that their users would cast them aside after use, rather than sharpen and reuse them.
But who was doing the eating? That’s where things get tricky. The tools found at the site were made about 50,000 years before the emergence of Homo sapiens. The location doesn’t narrow things down much, as several hominin species, including Homo erectus or Homo heidelbergensis would have passed through the Middle East on their journey from their African Birthplace to Eurasia. And no remains have been found at the site to clear things up.
Whoever the hungry hominins were, their diverse diet is surprising, considering that most Homo species (aside from our own) were thought to be specialists. But it was likely their adventurous eating that allowed these hominins to subsist in their increasingly arid environment.